Ion-exchange of Ni2+ ions in siliceous ZSM-5 

 -  Studies in surface Science and catalysis, 49, p.825-833, 1989 .
<br/><br/> Ion exchange of Ni2+ and K+ ions in siliceous ZSM-5 with widely varying aluminium contents (20<Si/A1<250)has been studied. Whereas regardless of the aluminium content near-stoichiometric exchange can be achieved with the mono- valent K+ ions, only limited exchange is observed with the divalent Ni2+ ions With decreasing aluminium content the degree of Ni2+ exchange drops markedly. These results are interpreted using a model which relates the position of the extra framework Ni2+ ions to a specific configuration of the aluminium ions with regard to each other in the lattice.